To find the heat energy required to raise the temperature of 1 kg of water from 0°C to 100°C, we can use the formula:

Q = mcΔT

Where:
Q = heat energy (in joules)
m = mass of the water (in kg) = 1 kg
c = specific heat capacity of water = 4186 J/kg°C
ΔT = change in temperature = (100°C - 0°C) = 100°C

Plugging in the values, we get:

Q = 1 kg 4186 J/kg°C 100°C
Q = 418600 J

Therefore, the heat energy required to raise the temperature of 1 kg of water from 0°C to 100°C is 418600 Joules.